1. Human Heredity

2. Do Now Read the statements below. Determine if they are true or false. Record answer. Read the statements below. Determine if they are true or false. Record answer. 1. The father determines the gender of the child. 1. The father determines the gender of the child. 2. Individuals may transmit characteristics to their offspring which they themselves do not show. 2. Individuals may transmit characteristics to their offspring which they themselves do not show. 3. Identical twins always are of the same gender. 3. Identical twins always are of the same gender.

3. Discuss 1. Which questions did we miss? 1. Which questions did we miss? Why? Why? 2. Why is it helpful to understand human heredity? 2. Why is it helpful to understand human heredity?

4. Vocab Carrier nondisjunction Pedigree telomere Incomplete dominance Codominance karyotype Multiple alleles polygenic trait Epistatis sex- linked trait Sex chromosome autosome

5. Team 1 vs Team 2 Pictonary Pictonary Each team will draw a word meaning on the board Each team will draw a word meaning on the board If your team gets the word in 45 seconds you win a point. If your team gets the word in 45 seconds you win a point. Flip flop between teams. Flip flop between teams.

6. Human Chromosomes Humans have 46 chromosomes- 23 pairs Humans have 46 chromosomes- 23 pairs Genotype of Female is XX Genotype of Female is XX Genotype of Male is XY Genotype of Male is XY

7. karyotype: picture of chromosomes

8. Most genetic disorders are caused by RECESSIVE alleles. Cystic fibrosis- large accumulation of muscus due to lack of protein. Cystic fibrosis- large accumulation of muscus due to lack of protein. Phenylketonuria (PKU)- lack enzyme that converts phenylalanine to tyrosine. Phenylketonuria (PKU)- lack enzyme that converts phenylalanine to tyrosine. Tay-Sachs- lack of enzyme that breaks down fat in the CNS Tay-Sachs- lack of enzyme that breaks down fat in the CNS Albinism- lack of pigment in skin. Albinism- lack of pigment in skin.

9. Cystic Fibrosis *Caused by a defect in a protein that results in an overproduction of muscus. *Favors bacterial infections because mucos clogs the body like the pancreas, lungs and digestive system. *1 in 20 white Americans are carriers.

10. Cystic Fibrosis cont… 1 in every 2000 children born to white Americans has this disorder. 1 in every 2000 children born to white Americans has this disorder. Without treatments, most children die before age 5. Without treatments, most children die before age 5. With treatments, can live into 20’s+ With treatments, can live into 20’s+ Treatment includes diet, meds, replacement enzymes and physical therapy Treatment includes diet, meds, replacement enzymes and physical therapy

11. Cystic Fibrosis

12. Tay-Sachs- DON’T WRITE *Lack enzyme breaks down fat in the CNS- fat collects on the brain. *No treatment or cure. Most will die before the age of 6. Found on chromosome #15 predominant in Eastern European Jewish decent. Found on chromosome #15 predominant in Eastern European Jewish decent.

13. Tay- Sachs cont…

14. Albinism *Absence of pigment melanin in hair, eyes and skin. *Absence of pigment melanin in hair, eyes and skin. *Affects eyesight *Affects eyesight

15. Albinism

16. Celiac Disease *Gluten cannot be broken down- protein in wheat, rye and barley. *Small intestine responds by attacking itself.

17. Disorders caused by dominant alleles: Huntington’s *Disease- effects nervous system. Huntington’s *Disease- effects nervous system. 1/10,000 people in U.S between ages 30-50 yrs old. 1/10,000 people in U.S between ages 30-50 yrs old. *Gradual loss of brain functions *Gradual loss of brain functions

18. Dwarfism/ Achondroplasia *Genetic disorder due to lack of growth hormone Little people is the PC term. Little people is the PC term. Many different forms not just height. Many different forms not just height. 75% are born to people of average height. 75% are born to people of average height.

19. Polydactyl- more than 5 digits on hand or foot

20. Top 10 Genetic Disorders. top 10 top 10 top 10 top 10

21. Caused by changes in DNA (mutations): Sickle-cell Anemia: amino acid is changed in hemoglobin to give cells a sickle shape. Blocks the flow of red blood cells. Sickle-cell Anemia: amino acid is changed in hemoglobin to give cells a sickle shape. Blocks the flow of red blood cells.

22. Sex-Linked Disorders- most commonly found in males Mostly on X chromosome (recessive) and since males have only one X chromosome they will express the disorder more often. Mostly on X chromosome (recessive) and since males have only one X chromosome they will express the disorder more often. Examples: Examples: Colorblindness Colorblindness Hemophilia Hemophilia Muscular Dystrophy Muscular Dystrophy

23. DON’T WRITE Some genes are located on the X chromosome. Females receive two alleles for these genes, but males only receive one. Some genes are located on the X chromosome. Females receive two alleles for these genes, but males only receive one. If the parent is a male, the genotype is automatically known. A colorblind male has to be b, since he only has one allele and colorblindness is recessive. A normal male must then be B If the parent is a male, the genotype is automatically known. A colorblind male has to be b, since he only has one allele and colorblindness is recessive. A normal male must then be B Females can be heterozygous for the colorblindness trait - they are called carriers. A female can be BB - normal, Bb - carrier, or bb - colorblind Females can be heterozygous for the colorblindness trait - they are called carriers. A female can be BB - normal, Bb - carrier, or bb - colorblind

24. The following shows a cross between a normal man and a woman who is a carrier

25. colorblindess test

26. a Y-linked trait

27. Chromosomal Disorders Nondisjunction: chromosomes fail to separate properly during meiosis (formation of gametes) Nondisjunction: chromosomes fail to separate properly during meiosis (formation of gametes)

28. Chromosomal Disorders Down Syndrome- extra chromosome on #21 (results in total of 47 chrom) Down Syndrome- extra chromosome on #21 (results in total of 47 chrom) Turner’s- only 1 sex chromosome and alters female development Turner’s- only 1 sex chromosome and alters female development Klinefelter’s- males with an extra X chromosome. Alters testosterone development. May cause infertility Klinefelter’s- males with an extra X chromosome. Alters testosterone development. May cause infertility

29. Down Syndrome- Extra chromosome on #21. Total of 47 chromosomes Down Syndrome- Extra chromosome on #21. Total of 47 chromosomes

30. Turner’s Only 1 X Only 1 X

31. Klinefelter”s Extra X Extra X

32. Karyotype A karyotype is an image of whole chromosomes stained during metaphase. A karyotype is an image of whole chromosomes stained during metaphase. Show identical genes on homologous chromosomes. Show identical genes on homologous chromosomes. Pairs are arranged by decreasing size. Pairs are arranged by decreasing size.

33. Down Syndrome Karyotype

34. Klinefelter’s Karyotype

35. Turner’s Karyotype

36. Karyotype activity You and a partner will assemble the Karyotype of your human in the envelope. You and a partner will assemble the Karyotype of your human in the envelope. 1. match up chromosomes 1. match up chromosomes 2. arrange by size 2. arrange by size 3. label # 1-23 pairs and each individual chromosome 3. label # 1-23 pairs and each individual chromosome 4. match up with known karyotypes and identify your human 4. match up with known karyotypes and identify your human 5. If they have a disorder list symptoms. 5. If they have a disorder list symptoms.

37. Pedigree A pedigree is a family history study. A pedigree is a family history study. If a trait is expressed the shape is darkened If a trait is expressed the shape is darkened If not shaded trait not expressed If not shaded trait not expressed Half shaded carrier but not expressed Half shaded carrier but not expressed

38. Pedigree—graphic representation of genetic inheritance. - Male= square - Female= circle - Shaded= has the disorder - Half shaded= carrier of disorder.

39. Activity Pick one of the case studies or page 300 Pick one of the case studies or page 300